One for the tuners?

I just received this press release, which I thought might interest a few of you

AVL DiTEST LAUNCHES DPM 800 - A REVOLUTIONARY DYNAMIC PRESSURE MEASUREMENT TOOL FOR THE MOTORSPORT MARKET

Stand E241 – Autosport Engineering Show, NEC, January 14/15

 

AVL DiTEST, a member of the renowned AVL List group of automotive companies, is launching a revolutionary new in-cylinder pressure transducer at the Autosport Engineering Show, NEC, Birmingham, January 14/15. Called the DPM 800 (DPM stands for Dynamic Pressure Measurement), the new product comprises a unique spark plug with built-in pressure sensor. The so called Piezo plug system will not only help motorsport teams tune their engines where and whenever they wish, but also accurately gauge wear rates and potential longevity as the season progresses.

Cylinder pressure transducers have traditionally required modifications to the cylinder head of the engine on test, so have been restricted to dyno use only. Where the AVL DiTEST technology differs, is that its sensor is built into a replacement spark plug, allowing engines to be tested at the circuit, in the workshop etc – ie wherever and whenever pressure readings are needed. There is an equally effective version for compression ignition engines, in which the pressure transducer replaces the engine’s glow plug.

 

The smallest sensor technology in the world

The other unique aspect of the technology comes courtesy of AVL DiTEST’s sister company PIEZOCRYST and concerns the sensor’s crystal that is key to the measurement process. Rather than the normal quartz type that is considerably bulkier and requires water cooling, the AVL DiTEST system utilises a Gallium Phosphate crystal. Artificially grown by PIEZOCRYST, this not only results in the smallest such sensor technology in the world, but one that can operate stably at very high temperatures without any extra cooling.

The new DPM 800 motorsport package comprises the Piezo plug, an amplifier, an oscilloscope (AVL DiTEST DiSCOPE 802) and the related software. To test the performance in a particular cylinder one merely replaces the existing spark plug and links the Piezo plug to the rest of the AVL DiTEST equipment. Accurate pressure readings can then be taken whatever the engine temperature. Top Dead Centre (TDC) can be readily ascertained and pressure curves produced to allow optimisation of ignition timing and general performance.

 

Major savings could result

Some racing formulae require engines to last a whole season without rebuild. In such situations, the AVL DiTEST system can provide an invaluable guide to general wear and tear and help predict failures before they occur – the cost savings of which could clearly be considerable.

Its highly competitive price of 6,550 Euros (including plug, amplifier, oscilloscope and software), will bring such equipment within reach of the semi-professional motorsport fraternity for the first time. Moreover, the system is equally suitable for use by tuning companies, university test labs etc.

For further information on AVL DiTEST and its products log onto

www.avlditest.com

 

I just received this press release, which I thought might interest a few of you

Guess not

Guess not

i thaught it looked pretty cool mate , just had nothing worth saying about it

Bit like a high end det sensor, but obviously reveals far more info.

Looks good, bet its not cheap though

Looks good, bet its not cheap though

Correct, but surely it's worth it given the savings elsewhere?

Its highly competitive price of 6,550 Euros (including plug, amplifier, oscilloscope and software)

In plug transducers have been around for years, my bet is the 2JZ-GTE was mapped and developed with then from the start. They probably used a sensor from these people: http://www.kistler.com/gb_en-gb/engines/Engines-Measurement-Technology.html For sure the price has dropped a lot of late though, with others coming into the market. If you are serious you can use a none in plug transducer for far less cost if you are willing to machine the head. This is how Zytek developed F3000 race engines by probing in cylinder pressure rises:

Not sure why AVL are claiming that this is "unique". Maybe its uniqueness is that it's aimed at the tuning market?

Anyway, in-cylinder pressure measurement is THE way to do tuning, OEM fashion. We tend to steer clear of the sparkplug type sensors - I'm not actually sure why.

Imagine: Direct BMEP measurements without any of those messy fiddle factors required for wheel dynos - all without having to take your engine out and stick it on an engine dyno. That would sort out a lot of arguments (or maybe cause some new ones)!

For those that are reading this and scratching their heads, here is a link that may help on what this bit of kit does.

http://www.epi-eng.com/piston_engine_technology/bmep_performance_yardstick.htm

For those that are reading this and scratching their heads, here is a link that may help on what this bit of kit does.

http://www.epi-eng.com/piston_engine_technology/bmep_performance_yardstick.htm

Is there anything you can do to those calculations to account for boost? Ie to guestimate how accurate a dyno run figure is, putting is sample data of 600bhp, 7000rpm on a 3.0l comes back with a value of 370, does that sound reasonable for a single Supra running 1.6 BAR?

Actually, my earlier statement wasn't correct. As stated in that link you can't measure BMEP directly from cylinder pressures. What you measure is IMEP (Indicated Mean Effectove Pressure). BMEP is still measured at the flywheel. The difference between the two is FMEP (Friction Mean Effective Pressure).

IMEP is still a brilliant figure to work with for tuning, but it won't give you your flywheel HP directly unless you know (or can make an estimate of) the engine's FMEP.

Is there anything you can do to those calculations to account for boost? Ie to guestimate how accurate a dyno run figure is, putting is sample data of 600bhp, 7000rpm on a 3.0l comes back with a value of 370, does that sound reasonable for a single Supra running 1.6 BAR?

I'm afraid i haven't gone into the calculations much myself, i think Digsy is your man for verification.

I think the point being is that the device makes the fugue jiggling unnecessary.

Did find another Link that may be a Little more clear.

http://www.bmepfuelandtuning.com/html/what_is_bmep_.html

Is there anything you can do to those calculations to account for boost? Ie to guestimate how accurate a dyno run figure is, putting is sample data of 600bhp, 7000rpm on a 3.0l comes back with a value of 370, does that sound reasonable for a single Supra running 1.6 BAR?

No, there's no simple way to go from boost pressure to BMEP.

I did used to have a spreadsheet that attempted to scale an engine's performance from A to B by changing a few parameters (boost pressure being one of them) but in order to get sensible results out for B you had to have a very good knowledge of A. I tried it a few times using data from IanC's car but it never really worked properly so I gave up.

I also once had a serious go at calculating flywheel hp by using logged Emanage data for fuel flow and AFR, then working out how much fuel energy got converted into mechanical energy based on a data base of engine efficiencies. That was a disaster too.

There is a dyno math library for the AEM software but I never got round to trying it.

No, there's no simple way to go from boost pressure to BMEP.

 

I did used to have a spreadsheet that attempted to scale an engine's performance from A to B by changing a few parameters (boost pressure being one of them) but in order to get sensible results out for B you had to have a very good knowledge of A. I tried it a few times using data from IanC's car but it never really worked properly so I gave up.

 

I also once had a serious go at calculating flywheel hp by using logged Emanage data for fuel flow and AFR, then working out how much fuel energy got converted into mechanical energy based on a data base of engine efficiencies. That was a disaster too.

I guess if you consider a small turbo running at x PSI & a large turbo at x PSI there could be a huge bhp gap.